The overall objective of the proposed effort is to develop a novel process to remediate groundwater contaminated with toxic organics utilizing jet-induced cavitation. A wide variety of toxic substances in aquifers at many Superfund sites pose serious problems to the nation's fresh water supply. Contaminated groundwater is a particular threat to the health of those relying on well water. Typically, the contamination is present in very large volumes of water at dilute concentrations such that efficient, rapid, and inexpensive processing is critical. Cavitation produces sonochemically-activated reactions in water, resulting in the creation of highly effective oxidizing hydroxyl radicals, and promotes a wide range of reactions including oxidation of organic compounds. Cavitation induced by specially designed jets have been shown to oxidize compounds in the laboratory with two orders of magnitude greater energy efficiency than ultrasonic devices. Phase I will investigate the feasibility of oxidizing selected compounds of high priority for groundwater remediation utilizing special cavitating jets. Using a combination of experiments and modeling, the characteristics and requirements of a practical scale system will be estimated. Phase II will expand the number of compounds investigated, refine scaling laws, and address larger and practical scale implementation issues.